This morning, abc news can confirm that james gandolfini was staying at the h in central holm when he suffered a heart attack. It was his 13-year-old son, michael, who was vacationing here in rome, and alerted the star that he wasn't feeling well. They alerted the emergency services. We understand that gandolfini was alive when he was rushed to rome's main hospital in an ambulance at 10:40 p.M. Paramedics began to resuscitate him in the ambulance, as well as at the hospital, when he arrived, for a good 40 minutes after he arrived before he was pronounced dead. The cause of death is not yet known. It hasn't been confirmed. An autopsy has to take place. And according to italian law, it has to take place 24 hours after the person has been declared dead. We'll get a clearer picture of what happened perhaps tomorrow. But this morning, gandolfini's body remains in rome's main morgue. Robin? Lama, thank you. His fellow actors, all of us stunned by his sudden death. Chris connelly is in los angeles with a look back at his life. Good morning, chris. Reporter: Good morning, robin. You know, you think of james gandolfini. He used anger when he played tony soprano, like an artist uses a paint brush, to create one of the most iconic characters of our time. On a series, it changed the way we think about television. You want to what? You don't want to what? Reporter: Through six stupendous seasons on "the sopranos," james gandolfini took the mythic character of the mob boss and brought it into the modern age. Filling tony soprano's complicated life, with vivid, complicated emotion. As he grapples with the consequences of his work with those who he loved. Are you in the mafia? Reporter: Gandolfini captured a man in turmoil. Ordering a hit. This guy, cannot come back to tell this story. Reporter: Sparring with carmela, his wife. Raging at his rivals and associates. And what we are here for, in the end, is to put food on the table for our families. Reporter: Reflecting with his shrink, dr. Melfy. You know my feelings. Every day is a gift. Reporter: Gandolfini found ways to give tony soprano an inner life, a depth of feeling. I have some dark moments. And I think it's useful that i have a place to put them. Reporter: His performance became the most acclaimed of its era. Gandolfini won three best actor emmys and three screen actors guild awards. Like carroll o'connor as archie bunker on "all in the family," gandolfini was all but a tony soprano type. He produced documents on ptsd on soldiers and men and women who served in iraq. He was great on the big screen. From the quentin tarantino penned "true romance," to the cohen brothers black and white drama, "the man who wasn't there." Someday soon, you're going to have families of your own. And if you're lucky, you'll remember the little moments. Reporter: But it is, as tony soprano, that his work will forever be treasured. Still, a landmark portrayal, even six years after "the sopranos" last episode, that provocative and enigmatic finale. James gandolfini leaves behind the wife and two children. And an 8-month-old daughter. He died yesterday in rome, at

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